The kernel would like to have all stack VLA usage removed[1]. This is a test function so the execution speed is not critical. We can allocate memory for this buffer instead of using a VLA. If kmalloc() fails just return.
Allocate buffer with kmalloc(). [1]: https://lkml.org/lkml/2018/3/7/621 Signed-off-by: Tobin C. Harding <m...@tobin.cc> --- Kees is this annoying you, CC'ing you an all my VLA patches? drivers/of/unittest.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c index 1991fe4319f5..38cbc343b7da 100644 --- a/drivers/of/unittest.c +++ b/drivers/of/unittest.c @@ -254,12 +254,18 @@ static void __init of_unittest_check_tree_linkage(void) static void __init of_unittest_printf_one(struct device_node *np, const char *fmt, const char *expected) { - unsigned char buf[strlen(expected)+10]; + unsigned char *buf; + int buf_size; int size, i; + buf_size = strlen(expected) + 10; + buf = kmalloc(buf_size, GFP_KERNEL); + if (!buf) + return; + /* Baseline; check conversion with a large size limit */ - memset(buf, 0xff, sizeof(buf)); - size = snprintf(buf, sizeof(buf) - 2, fmt, np); + memset(buf, 0xff, buf_size); + size = snprintf(buf, buf_size - 2, fmt, np); /* use strcmp() instead of strncmp() here to be absolutely sure strings match */ unittest((strcmp(buf, expected) == 0) && (buf[size+1] == 0xff), @@ -270,12 +276,13 @@ static void __init of_unittest_printf_one(struct device_node *np, const char *fm size++; for (i = 0; i < 2; i++, size--) { /* Clear the buffer, and make sure it works correctly still */ - memset(buf, 0xff, sizeof(buf)); + memset(buf, 0xff, buf_size); snprintf(buf, size+1, fmt, np); unittest(strncmp(buf, expected, size) == 0 && (buf[size+1] == 0xff), "snprintf failed; size=%i fmt='%s' expected='%s' rslt='%s'\n", size, fmt, expected, buf); } + kfree(buf); } static void __init of_unittest_printf(void) -- 2.7.4
